Mp3 is the most popular and widespread audio format. It was created by MPEG team in the 90s of the last century. MP3 format provides the quality of sound reproduction, similar to the original sound. The MP3 format is based on a lossless compression algorithm made to reduce the data size. In other words, music streams are compressed and deleted in the format that are somehow similar for listening on devices of common use.
Apple Lossless also known as Apple Lossless Encoder is an open audio codec for lossless compression of digital music developed by Apple in 2004. Audio data is stored in an MP4 container with m4a extension. This codec is similar to other lossless codecs such as FLAC. Every year this format becomes more popular as it is used in iTunes and in all media devices from Apple.